<!DOCTYPE html>
<html>
<head>
<title>Swim Lanes</title>
<meta name="description" content="Horizontal swim lanes and pools with collapsible lanes and limited dragging." />
<!-- Copyright 1998-2016 by Northwoods Software Corporation. -->
<meta charset="UTF-8">
<script src="go.js"></script>
<link href="../assets/css/goSamples.css" rel="stylesheet" type="text/css" />  <!-- you don't need to use this -->
<script src="goSamples.js"></script>  <!-- this is only for the GoJS Samples framework -->
<script id="code">
  // These parameters need to be set before defining the templates.
  var MINLENGTH = 200;  // this controls the minimum length of any swimlane
  var MINBREADTH = 20;  // this controls the minimum breadth of any non-collapsed swimlane

  // some shared functions

  // this may be called to force the lanes to be laid out again
  function relayoutLanes() {
    myDiagram.nodes.each(function(lane) {
      if (!(lane instanceof go.Group)) return;
      if (lane.category === "Pool") return;
      lane.layout.isValidLayout = false;  // force it to be invalid
    });
    myDiagram.layoutDiagram();
  }

  // this is called after nodes have been moved or lanes resized, to layout all of the Pool Groups again
  function relayoutDiagram() {
    myDiagram.layout.invalidateLayout();
    myDiagram.findTopLevelGroups().each(function(g) { if (g.category === "Pool") g.layout.invalidateLayout(); });
    myDiagram.layoutDiagram();
  }

  // compute the minimum size of a Pool Group needed to hold all of the Lane Groups
  function computeMinPoolSize(pool) {
    // assert(pool instanceof go.Group && pool.category === "Pool");
    var len = MINLENGTH;
    pool.memberParts.each(function(lane) {
      // pools ought to only contain lanes, not plain Nodes
      if (!(lane instanceof go.Group)) return;
      var holder = lane.placeholder;
      if (holder !== null) {
        var sz = holder.actualBounds;
        len = Math.max(len, sz.width);
      }
    });
    return new go.Size(len, NaN);
  }

  // compute the minimum size for a particular Lane Group
  function computeLaneSize(lane) {
    // assert(lane instanceof go.Group && lane.category !== "Pool");
    var sz = computeMinLaneSize(lane);
    if (lane.isSubGraphExpanded) {
      var holder = lane.placeholder;
      if (holder !== null) {
        var hsz = holder.actualBounds;
        sz.height = Math.max(sz.height, hsz.height);
      }
    }
    // minimum breadth needs to be big enough to hold the header
    var hdr = lane.findObject("HEADER");
    if (hdr !== null) sz.height = Math.max(sz.height, hdr.actualBounds.height);
    return sz;
  }

  // determine the minimum size of a Lane Group, even if collapsed
  function computeMinLaneSize(lane) {
    if (!lane.isSubGraphExpanded) return new go.Size(MINLENGTH, 1);
    return new go.Size(MINLENGTH, MINBREADTH);
  }


  // define a custom ResizingTool to limit how far one can shrink a lane Group
  function LaneResizingTool() {
    go.ResizingTool.call(this);
  }
  go.Diagram.inherit(LaneResizingTool, go.ResizingTool);

  LaneResizingTool.prototype.isLengthening = function() {
    return (this.handle.alignment === go.Spot.Right);
  };

  /** @override */
  LaneResizingTool.prototype.computeMinSize = function() {
    var lane = this.adornedObject.part;
    // assert(lane instanceof go.Group && lane.category !== "Pool");
    var msz = computeMinLaneSize(lane);  // get the absolute minimum size
    if (this.isLengthening()) {  // compute the minimum length of all lanes
      var sz = computeMinPoolSize(lane.containingGroup);
      msz.width = Math.max(msz.width, sz.width);
    } else {  // find the minimum size of this single lane
      var sz = computeLaneSize(lane);
      msz.width = Math.max(msz.width, sz.width);
      msz.height = Math.max(msz.height, sz.height);
    }
    return msz;
  };

  /** @override */
  LaneResizingTool.prototype.resize = function(newr) {
    var lane = this.adornedObject.part;
    if (this.isLengthening()) {  // changing the length of all of the lanes
      lane.containingGroup.memberParts.each(function(lane) {
        if (!(lane instanceof go.Group)) return;
        var shape = lane.resizeObject;
        if (shape !== null) {  // set its desiredSize length, but leave each breadth alone
          shape.width = newr.width;
        }
      });
    } else {  // changing the breadth of a single lane
      go.ResizingTool.prototype.resize.call(this, newr);
    }
    relayoutDiagram();  // now that the lane has changed size, layout the pool again
  };
  // end LaneResizingTool class


  // define a custom grid layout that makes sure the length of each lane is the same
  // and that each lane is broad enough to hold its subgraph
  function PoolLayout() {
    go.GridLayout.call(this);
    this.cellSize = new go.Size(1, 1);
    this.wrappingColumn = 1;
    this.wrappingWidth = Infinity;
    this.isRealtime = false;  // don't continuously layout while dragging
    this.alignment = go.GridLayout.Position;
    // This sorts based on the location of each Group.
    // This is useful when Groups can be moved up and down in order to change their order.
    this.comparer = function(a, b) {
      var ay = a.location.y;
      var by = b.location.y;
      if (isNaN(ay) || isNaN(by)) return 0;
      if (ay < by) return -1;
      if (ay > by) return 1;
      return 0;
    };
  }
  go.Diagram.inherit(PoolLayout, go.GridLayout);

  /** @override */
  PoolLayout.prototype.doLayout = function(coll) {
    var diagram = this.diagram;
    if (diagram === null) return;
    diagram.startTransaction("PoolLayout");
    var pool = this.group;
    if (pool !== null && pool.category === "Pool") {
      // make sure all of the Group Shapes are big enough
      var minsize = computeMinPoolSize(pool);
      pool.memberParts.each(function(lane) {
        if (!(lane instanceof go.Group)) return;
        if (lane.category !== "Pool") {
          var shape = lane.resizeObject;
          if (shape !== null) {  // change the desiredSize to be big enough in both directions
            var sz = computeLaneSize(lane);
            shape.width = (isNaN(shape.width) ? minsize.width : Math.max(shape.width, minsize.width));
            shape.height = (!isNaN(shape.height)) ? Math.max(shape.height, sz.height) : sz.height;
            var cell = lane.resizeCellSize;
            if (!isNaN(shape.width) && !isNaN(cell.width) && cell.width > 0) shape.width = Math.ceil(shape.width / cell.width) * cell.width;
            if (!isNaN(shape.height) && !isNaN(cell.height) && cell.height > 0) shape.height = Math.ceil(shape.height / cell.height) * cell.height;
          }
        }
      });
    }
    // now do all of the usual stuff, according to whatever properties have been set on this GridLayout
    go.GridLayout.prototype.doLayout.call(this, coll);
    diagram.commitTransaction("PoolLayout");
  };
  // end PoolLayout class


  function init() {
    if (window.goSamples) goSamples();  // init for these samples -- you don't need to call this
    var $ = go.GraphObject.make;

    myDiagram =
      $(go.Diagram, "myDiagramDiv",
        {
          // start everything in the middle of the viewport
          initialContentAlignment: go.Spot.Center,
          // use a custom ResizingTool (along with a custom ResizeAdornment on each Group)
          resizingTool: new LaneResizingTool(),
          // use a simple layout that ignores links to stack the top-level Pool Groups next to each other
          layout: $(PoolLayout),
          // don't allow dropping onto the diagram's background unless they are all Groups (lanes or pools)
          mouseDragOver: function(e) {
            if (!e.diagram.selection.all(function(n) { return n instanceof go.Group; })) {
              e.diagram.currentCursor = 'not-allowed';
            }
          },
          mouseDrop: function(e) {
            if (!e.diagram.selection.all(function(n) { return n instanceof go.Group; })) {
              e.diagram.currentTool.doCancel();
            }
          },
          // a clipboard copied node is pasted into the original node's group (i.e. lane).
          "commandHandler.copiesGroupKey": true,
          // automatically re-layout the swim lanes after dragging the selection
          "SelectionMoved": relayoutDiagram,  // this DiagramEvent listener is
          "SelectionCopied": relayoutDiagram, // defined above
          "animationManager.isEnabled": false,
          // enable undo & redo
          "undoManager.isEnabled": true
        });

    // this is a Part.dragComputation function for limiting where a Node may be dragged
    function stayInGroup(part, pt, gridpt) {
      // don't constrain top-level nodes
      var grp = part.containingGroup;
      if (grp === null) return pt;
      // try to stay within the background Shape of the Group
      var back = grp.resizeObject;
      if (back === null) return pt;
      // allow dragging a Node out of a Group if the Shift key is down
      if (part.diagram.lastInput.shift) return pt;
      var p1 = back.getDocumentPoint(go.Spot.TopLeft);
      var p2 = back.getDocumentPoint(go.Spot.BottomRight);
      var b = part.actualBounds;
      var loc = part.location;
      // find the padding inside the group's placeholder that is around the member parts
      var m = grp.placeholder.padding;
      // now limit the location appropriately
      var x = Math.max(p1.x + m.left, Math.min(pt.x, p2.x - m.right - b.width - 1)) + (loc.x-b.x);
      var y = Math.max(p1.y + m.top, Math.min(pt.y, p2.y - m.bottom - b.height - 1)) + (loc.y-b.y);
      return new go.Point(x, y);
    }

    myDiagram.nodeTemplate =
      $(go.Node, "Auto",
        new go.Binding("location", "loc", go.Point.parse).makeTwoWay(go.Point.stringify),
        $(go.Shape, "Rectangle",
          { fill: "white", portId: "", cursor: "pointer", fromLinkable: true, toLinkable: true }),
        $(go.TextBlock, { margin: 5 },
          new go.Binding("text", "key")),
        { dragComputation: stayInGroup } // limit dragging of Nodes to stay within the containing Group, defined above
      );

    function groupStyle() {  // common settings for both Lane and Pool Groups
      return [
        {
          layerName: "Background",  // all pools and lanes are always behind all nodes and links
          background: "transparent",  // can grab anywhere in bounds
          movable: true, // allows users to re-order by dragging
          copyable: false,  // can't copy lanes or pools
          avoidable: false,  // don't impede AvoidsNodes routed Links
          minLocation: new go.Point(NaN, -Infinity),  // only allow vertical movement
          maxLocation: new go.Point(NaN, Infinity)
        },
        new go.Binding("location", "loc", go.Point.parse).makeTwoWay(go.Point.stringify)
      ];
    }

    // hide links between lanes when either lane is collapsed
    function updateCrossLaneLinks(group) {
      group.findExternalLinksConnected().each(function(l) {
        l.visible = (l.fromNode.isVisible() && l.toNode.isVisible());
      });
    }

    // each Group is a "swimlane" with a header on the left and a resizable lane on the right
    myDiagram.groupTemplate =
      $(go.Group, "Horizontal", groupStyle(),
        {
          selectionObjectName: "SHAPE",  // selecting a lane causes the body of the lane to be highlit, not the label
          resizable: true, resizeObjectName: "SHAPE",  // the custom resizeAdornmentTemplate only permits two kinds of resizing
          layout: $(go.LayeredDigraphLayout,  // automatically lay out the lane's subgraph
                    {
                      isInitial: false,  // don't even do initial layout
                      isOngoing: false,  // don't invalidate layout when nodes or links are added or removed
                      direction: 0,
                      columnSpacing: 10,
                      layeringOption: go.LayeredDigraphLayout.LayerLongestPathSource
                    }),
          computesBoundsAfterDrag: true,  // needed to prevent recomputing Group.placeholder bounds too soon
          computesBoundsIncludingLinks: false,  // to reduce occurrences of links going briefly outside the lane
          computesBoundsIncludingLocation: true,  // to support empty space at top-left corner of lane
          handlesDragDropForMembers: true,  // don't need to define handlers on member Nodes and Links
          mouseDrop: function(e, grp) {  // dropping a copy of some Nodes and Links onto this Group adds them to this Group
            if (!e.shift) return;  // cannot change groups with an unmodified drag-and-drop
            // don't allow drag-and-dropping a mix of regular Nodes and Groups
            if (!e.diagram.selection.any(function(n) { return n instanceof go.Group; })) {
              var ok = grp.addMembers(grp.diagram.selection, true);
              if (ok) {
                updateCrossLaneLinks(grp);
              } else {
                grp.diagram.currentTool.doCancel();
              }
            } else {
              e.diagram.currentTool.doCancel();
            }
          },
          subGraphExpandedChanged: function(grp) {
            var shp = grp.resizeObject;
            if (grp.diagram.undoManager.isUndoingRedoing) return;
            if (grp.isSubGraphExpanded) {
              shp.height = grp._savedBreadth;
            } else {
              grp._savedBreadth = shp.height;
              shp.height = NaN;
            }
            updateCrossLaneLinks(grp);
          }
        },
        new go.Binding("isSubGraphExpanded", "expanded").makeTwoWay(),
        // the lane header consisting of a Shape and a TextBlock
        $(go.Panel, "Horizontal",
          { name: "HEADER",
            angle: 270,  // maybe rotate the header to read sideways going up
            alignment: go.Spot.Center },
          $(go.Panel, "Horizontal",  // this is hidden when the swimlane is collapsed
            new go.Binding("visible", "isSubGraphExpanded").ofObject(),
            $(go.Shape, "Diamond",
              { width: 8, height: 8, fill: "white" },
              new go.Binding("fill", "color")),
            $(go.TextBlock,  // the lane label
              { font: "bold 13pt sans-serif", editable: true, margin: new go.Margin(2, 0, 0, 0) },
              new go.Binding("text", "text").makeTwoWay())
          ),
          $("SubGraphExpanderButton", { margin: 5 })  // but this remains always visible!
        ),  // end Horizontal Panel
        $(go.Panel, "Auto",  // the lane consisting of a background Shape and a Placeholder representing the subgraph
          $(go.Shape, "Rectangle",  // this is the resized object
            { name: "SHAPE", fill: "white" },
            new go.Binding("fill", "color"),
            new go.Binding("desiredSize", "size", go.Size.parse).makeTwoWay(go.Size.stringify)),
          $(go.Placeholder,
            { padding: 12, alignment: go.Spot.TopLeft }),
          $(go.TextBlock,  // this TextBlock is only seen when the swimlane is collapsed
            { name: "LABEL",
              font: "bold 13pt sans-serif", editable: true,
              angle: 0, alignment: go.Spot.TopLeft, margin: new go.Margin(2, 0, 0, 4) },
            new go.Binding("visible", "isSubGraphExpanded", function(e) { return !e; }).ofObject(),
            new go.Binding("text", "text").makeTwoWay())
        )  // end Auto Panel
      );  // end Group

    // define a custom resize adornment that has two resize handles if the group is expanded
    myDiagram.groupTemplate.resizeAdornmentTemplate =
      $(go.Adornment, "Spot",
        $(go.Placeholder),
        $(go.Shape,  // for changing the length of a lane
          {
            alignment: go.Spot.Right,
            desiredSize: new go.Size(7, 50),
            fill: "lightblue", stroke: "dodgerblue",
            cursor: "col-resize"
          },
          new go.Binding("visible", "", function(ad) { return ad.adornedPart.isSubGraphExpanded; }).ofObject()),
        $(go.Shape,  // for changing the breadth of a lane
          {
            alignment: go.Spot.Bottom,
            desiredSize: new go.Size(50, 7),
            fill: "lightblue", stroke: "dodgerblue",
            cursor: "row-resize"
          },
          new go.Binding("visible", "", function(ad) { return ad.adornedPart.isSubGraphExpanded; }).ofObject())
      );

    myDiagram.groupTemplateMap.add("Pool",
      $(go.Group, "Auto", groupStyle(),
        { // use a simple layout that ignores links to stack the "lane" Groups on top of each other
          layout: $(PoolLayout, { spacing: new go.Size(0, 0) })  // no space between lanes
        },
        $(go.Shape,
          { fill: "white" },
          new go.Binding("fill", "color")),
        $(go.Panel, "Table",
          { defaultColumnSeparatorStroke: "black" },
          $(go.Panel, "Horizontal",
            { column: 0, angle: 270 },
            $(go.TextBlock,
              { font: "bold 16pt sans-serif", editable: true, margin: new go.Margin(2, 0, 0, 0) },
              new go.Binding("text").makeTwoWay())
          ),
          $(go.Placeholder,
            { column: 1 })
        )
      ));

    myDiagram.linkTemplate =
      $(go.Link,
        { routing: go.Link.AvoidsNodes, corner: 5 },
        { relinkableFrom: true, relinkableTo: true },
        $(go.Shape),
        $(go.Shape, { toArrow: "Standard" })
      );

    // define some sample graphs in some of the lanes
    myDiagram.model = new go.GraphLinksModel(
    [ // node data
      { key: "Pool1", text: "Pool", isGroup: true, category: "Pool" },
      { key: "Pool2", text: "Pool2", isGroup: true, category: "Pool" },
      { key: "Lane1", text: "Lane1", isGroup: true, group: "Pool1", color: "lightblue" },
      { key: "Lane2", text: "Lane2", isGroup: true, group: "Pool1", color: "lightgreen" },
      { key: "Lane3", text: "Lane3", isGroup: true, group: "Pool1", color: "lightyellow" },
      { key: "Lane4", text: "Lane4", isGroup: true, group: "Pool1", color: "orange" },
      { key: "oneA", group: "Lane1" },
      { key: "oneB", group: "Lane1" },
      { key: "oneC", group: "Lane1" },
      { key: "oneD", group: "Lane1" },
      { key: "twoA", group: "Lane2" },
      { key: "twoB", group: "Lane2" },
      { key: "twoC", group: "Lane2" },
      { key: "twoD", group: "Lane2" },
      { key: "twoE", group: "Lane2" },
      { key: "twoF", group: "Lane2" },
      { key: "twoG", group: "Lane2" },
      { key: "fourA", group: "Lane4" },
      { key: "fourB", group: "Lane4" },
      { key: "fourC", group: "Lane4" },
      { key: "fourD", group: "Lane4" },
      { key: "Lane5", text: "Lane5", isGroup: true, group: "Pool2", color: "lightyellow" },
      { key: "Lane6", text: "Lane6", isGroup: true, group: "Pool2", color: "lightgreen" },
      { key: "fiveA", group: "Lane5" },
      { key: "sixA", group: "Lane6" }
    ],
    [ // link data
      { from: "oneA", to: "oneB" },
      { from: "oneA", to: "oneC" },
      { from: "oneB", to: "oneD" },
      { from: "oneC", to: "oneD" },
      { from: "twoA", to: "twoB" },
      { from: "twoA", to: "twoC" },
      { from: "twoA", to: "twoF" },
      { from: "twoB", to: "twoD" },
      { from: "twoC", to: "twoD" },
      { from: "twoD", to: "twoG" },
      { from: "twoE", to: "twoG" },
      { from: "twoF", to: "twoG" },
      { from: "fourA", to: "fourB" },
      { from: "fourB", to: "fourC" },
      { from: "fourC", to: "fourD" }
    ]);
    // force all lanes' layouts to be performed
    relayoutLanes();
  }  // end init

  // Show the diagram's model in JSON format
  function save() {
    document.getElementById("mySavedModel").value = myDiagram.model.toJson();
    myDiagram.isModified = false;
  }
  function load() {
    myDiagram.model = go.Model.fromJson(document.getElementById("mySavedModel").value);
    myDiagram.delayInitialization(relayoutDiagram);
  }
</script>
</head>
<body onload="init()">
<div id="sample">
  <h3>GoJS Swim Lanes</h3>
  <div id="myDiagramDiv" style="border: solid 1px blue; width:100%; height:700px;"></div>
  <p>
    In this design each swimlane is implemented by a <a>Group</a>, and all lanes are inside a "Pool" Group.
    Each lane Group has its own <a>Group.layout</a>, which in this case is a <a>LayeredDigraphLayout</a>.
    Each pool Group has its own custom <a>GridLayout</a> that arranges all of its lanes in a vertical stack.
    That custom layout makes sure all of the pool's lanes have the same length.
  </p>
  <p>
    When dragging nodes note that the nodes are limited to stay within the lanes.
    This is implemented by a custom <a>Part.dragComputation</a> function, here named <b>stayInGroup</b>.
    Hold down the Shift key while dragging simple nodes to move the selection to another lane.
    Lane groups cannot be moved between pool groups.
  </p>
  <p>
    A Group (i.e. swimlane) is movable but not copyable.
    When the user moves a lane up or down the lanes automatically re-order.
    You can prevent lanes from being moved and thus re-ordered by setting Group.movable to false.
  </p>
  <p>
    Each Group is collapsible.
    The previous breadth of that lane is saved in the _savedBreadth property, to be restored when expanded.
  </p>
  <p>
    When a Group/lane is selected, its custom <a>Part.resizeAdornmentTemplate</a>
    gives it a broad resize handle at the bottom of the Group
    and a broad resize handle at the right side of the Group.
    This allows the user to resize the "breadth" of the selected lane
    as well as the "length" of all of the lanes.
    However, the custom <a>ResizingTool</a> prevents the lane from being too narrow
    to hold the <a>Group.placeholder</a> that represents the subgraph,
    and it prevents the lane from being too short to hold any of the contents of the lanes.
    Each Group/lane is also has a <a>GraphObject.minSize</a> to keep it from
    being too narrow even if there are no member <a>Part</a>s at all.
  </p>
  <p>
    A different sample has its swim lanes vertically oriented: <a href="swimLanesVertical.html">Swim Lanes (vertical)</a>.
  </p>
  <button onclick="relayoutLanes()">Layout</button>
  <button id="SaveButton" onclick="save()">Save</button>
  <button onclick="load()">Load</button>
  Diagram Model saved in JSON format:
  <br />
  <textarea id="mySavedModel" style="width:100%;height:300px"></textarea>
</div>
</body>
</html>